444 Tricotylous Races. 
Proportion of tricotyls in percentages 10 20 30 40 50 60 70 80 90 
Number of tricotylous individuals 1 611 14 10 1 
Number of atavistic individuals 1 4 3 10 11 11 6 
Calculated for the whole progeny 1 4 4 19 27 32 21 1 
The average value for the tricotyls is 72% and of the 
atavists 60%, which latter figure is of itself high enough 
for an intermediate race. The last row was obtained 
by means of a correction of the values of the tricotyls, 
since too small a number of these had been cultivated in 
comparison with the atavists. The whole curve is ob- 
viously monomorphic although much flattened. 
A curve with such a great amplitude indicates a cor- 
responding high variability and therefore also a consider- 
able susceptibility to external influences, as we have found 
in several instances to be the case with intermediate races. 
To this great amplitude also the fact is due that se- 
lection, however stringent, never quite eliminates the 
lower values. Even when the apex of the curve is be- 
tween 60 and 70%, values as low as 25% may still 
occur. In such cases the curve has a "sweep" to the 
atavistic side, and thus differs most conspicuously from 
the curves of the half race, the shape of which might be 
considered as its mirrored image ; but as I shall come 
back to this point when I deal with syncotylous races, 
I shall not give any instances now. 
7. PARTIAL VARIABILITY OF TRICOTYLY. 
In experiments with tricotylous races the hereditary 
capacity or value is, as we have seen, the main character 
subjected to selection. This term indicates the number 
of tricotylous seedlings in the harvest. The seeds of 
each individual are saved and sown separately, and then 
recorded after germination. Whether the individual it- 
